Douglas Hardy usually thinks in increments of a century. The climate scientist at the University of Massachusetts Amherst has for 13 years been trekking to the top of Mount Kilimanjaro to take measurements that will help him understand the record of environmental change embedded in 11,000-year-old cylinders of ice drilled out of glaciers.

Lately, though, he has been obsessing about the weather on an hourly basis, thinking about the fluctuations in wind speed over a single day.

The change in Hardy’s attention began more than a year ago, when he received a cryptic e-mail from a man in South Africa who sells instruments for weather stations. A client was interested in setting up a weather station at Kilimanjaro’s summit to aid in some kind of paragliding stunt. They were consulting Hardy because of his expertise in understanding the weather patterns atop the roof of Africa.

He responded like a scientist: The weather at the mountain top, Hardy knew from his research, was highly variable from year to year. Six months of data from a new weather station would not only put a redundant set of equipment on the mountain, but would hardly be enough of a long view to provide real insight into how to pull off such a spectacle.

Hardy thought it might end there. But on Tuesday, 100 paragliders are scheduled to launch a record-breaking spectacle, with colorful parachutes clustering and riding drafts of air down to the plain below — a roughly 16,000-foot journey — after consulting with Hardy on the right time of year and the fluctuations in weather conditions.